1. Field of the Invention
The present invention relates to a piezoelectric fiber composite, a preparation method thereof, a magnetoelectric laminate composite including the piezoelectric fiber composite, a manufacturing method thereof and a piezoelectric device including the piezoelectric fiber composite or the magnetoelectric laminate composite. More particularly, the present invention relates to a single-crystal piezoelectric fiber composite containing single-crystal piezoelectric fibers oriented in a specific direction, a preparation method thereof, a magnetoelectric laminate composite including the piezoelectric fiber composite, a manufacturing method thereof, and a piezoelectric device including the piezoelectric fiber composite or the magnetoelectric laminate composite.
2. Description of the Related Art
Piezoelectric materials are being widely utilized in sensors, actuators, energy harvesting devices, ultrasonic instruments, etc. using piezoelectric effects for converting external stress into an electric signal or an electric input into a mechanical output.
However, most piezoelectric materials are ceramic materials, and thus limitations are imposed on application into various shapes and usages thereof due to the intrinsic brittleness of ceramic materials.
Hence, research is ongoing into composites configured such that piezoelectric ceramic fibers are included in a flexible matrix made of a polymer material, and a typical example of such a composite includes a macro fiber composite (MFC) [Patent Document 0001]. Also, an actuator formed using MFC is known [Patent Document 0002].
However, since a piezoelectric fiber composite such as MFC includes the polymer matrix between electrodes and piezoelectric fibers, it is difficult to predict and design the control and operation of devices; furthermore, high driving voltage is required to operate the device including such a composite, which is very undesirable.
Moreover, a piezoelectric fiber composite such as MFC is problematic because it is impossible to maximize piezoelectric properties that vary depending on the crystal orientation of the piezoelectric material, due to the use of ceramic piezoelectric fiber materials.
Accordingly, there is need for composites useful in fabrication of energy harvesting devices as well as sensors or actuators by solving the aforementioned problems while keeping the known advantages of the piezoelectric fiber composite.